Not Sure What Happened ?

[TRXaddict]

Ok so i was driving around and i was trying to make a video of some driving I'm going to try to upload it to youtube right now but until then ill explain what happened.

Driving around no issues, gear mesh is fine and no sounds that alert me my mesh is incorrect. and then I'm trying to do this jump i set up but i can't do it one handed on the radio so i pull the truck to the side and lay the camera on a lump of dirt so you guys can see me try to jump it.

Then a few seconds later the camera is aimed and all you hear is my truck revving like CRAZY.. i just barley tapped the gas because i like to just kinda tap it once or twice before driving off from a start to listen for any mesh issues.

So anyways just literally after tapping the gas for a second the thing stays wide open and not moving. and i suddenly hear the spur gear strip and i plug the exhaust to shut it off.

The radios batteries arent dead and the receivers battery pack was fully charged right before i went driving. So I'm just wondering why it just suddenly stayed wide open and not moved ? Also i checked the diffs and transmission and everything spins freely no grinding nothing that seems out of place. and there were no issues during the video that at least made me think it was about to go bad...

Anyways.. I'm trying to upload the file now. soon as its done ill post on here

Thanks for reading !!

Kody

 

[MudSlinger33]

Did you check your servo to see if it had gotten stuck wide open?

 

[TRXaddict]

Did you check your servo to see if it had gotten stuck wide open?

Yeah after i shut the engine off i took the body off and tested the throttle/brake and everything moved smoothly with nothing like stuck.. but is it possible something made it be full brake while fullthrottle somehow ? like maybe somehow the brake lever had pressure and somehow when i tapped the gas maybe something made the throttle just suddenly go all the way open.

Also I'm trying to upload the video but the file is saying its corrupt. I'm gonna try to upload it on my mothers computer and then upload it on youtube so you can hear the way the truck sounds.

 

[shizcol]

Total dislike man.. I feel u. Are u usin the stock radio? I would reccomend getting a better radio. I bought this flysky gt3b and for the price it can not be beat. 60 bucks for the radio and 3 recievers. ( i run more then one rc lol)
That might be ur problem but who knows. I hope uncan figure it out

 

[TRXaddict]

^ yeah really sucks that this happened, my spur gear luck streak ran out. Almost all my nitro rc's never burned out one spur gear because i always had good mesh. but i mean if i could get an aftermarket radio i would for sure get a spektrum if i could afford it.

Awhile ago i heard some other members somewhere on here talk about replacing the throttle servo with the steering servo and it will improve your brake. well i got an upgraded steering servo and then put it on my Throttle/brake and i did notice a much stronger stopping power and i like it.. but maybe something just glitched or something jammed the throttle open while forcing the brake to be fully applied.

 

[shizcol]

Yeah spektrum is good stuff. I never heard of it being possible of the throttle and brake being on at the same time. I doubt thats even possible . Get a new spur and try again and see what happens

 

[TRXaddict]

Yeah neither did i, but if you notice on the throttle/brake servo.. the bell that attached to the top actually has a piece where if you push one end one and and another end another way you can do it.. its got some sort of spring in there where you can literally move one . one way and another the opposite .. I'm guessing.. some how the brake side got stuck and the throttle side got stuck the other way. because its 2 separate linkages for the brake and throttle compared to usual one rod controlling both. So thats my only guess, i put the stock throttle servo back in and so maybe next time it will just close back up.

But yeah the video every time i try to download it to my computer it just says the file is corrupted. -_____-

 

[Assassin]

Yeah neither did i, but if you notice on the throttle/brake servo.. the bell that attached to the top actually has a piece where if you push one end one and and another end another way you can do it.. its got some sort of spring in there where you can literally move one . one way and another the opposite .. I'm guessing.. some how the brake side got stuck and the throttle side got stuck the other way. because its 2 separate linkages for the brake and throttle compared to usual one rod controlling both. So thats my only guess, i put the stock throttle servo back in and so maybe next time it will just close back up.

But yeah the video every time i try to download it to my computer it just says the file is corrupted. -_____-

Check your clutch shoes, check your slipper clutch, to be good.

You want to look at the clutch bell bearings and see if there is any play, if the CB wobbled a bit, it may have locked up with the spur. You want to really make sure your clutch is all good. If you use the thick spur the ever so slight play may seem like a good mesh but periodically bind under odd conditions, more room for play with the Thin HS spur, if that's what you were using (surprised) just check the bearings for the clutch bell, inner and outer, and washers etc.


At low power on the RX or TX (But they still seem to work) at times if you make 2 inputs at the same time, it will only register one, like if you hit the gas then make a turn while still holding the gas the truck may not turn and stick WOT until you release both and make a single input "Brake". Not saying that happened, just putting it out there.

 

[TRXaddict]

Check your clutch shoes, check your slipper clutch, to be good.

You want to look at the clutch bell bearings and see if there is any play, if the CB wobbled a bit, it may have locked up with the spur. You want to really make sure your clutch is all good. If you use the thick spur the ever so slight play may seem like a good mesh but periodically bind under odd conditions, more room for play with the Thin HS spur, if that's what you were using (surprised) just check the bearings for the clutch bell, inner and outer, and washers etc.


At low power on the RX or TX (But they still seem to work) at times if you make 2 inputs at the same time, it will only register one, like if you hit the gas then make a turn while still holding the gas the truck may not turn and stick WOT until you release both and make a single input "Brake". Not saying that happened, just putting it out there.

Yeah thats another thing i checked is the CB shoes and bearings. everything seems ship shape. its just weird cuz the whole thing just suddenly went wide open just for a small tap of the throttle and after i shut it off and messed with the steering and throttle/brake it functioned properly.. just changed to the original throttle servo just because i wanted to see how it would be. but i mean it still functions fine.

 

[TaterX]

I bet the spur gear slipped. You may need a new spring, washer, and lock nut set for your spur. Look at the bushing in the spur gear and see if its shiny with circular scratches on the outside from the washer like it spun free as if the nut wasn't tight enough. I know this will cause it to rev high and sheer the teeth.

 

[TRXaddict]

but how would the spur gear cause more air/fuel to enter the engine to make it rev higher ? It didnt seem to rev wide open untill i just barley tapped the gas.

Also just held the gear over a lamp to see into the center piece in the spur gear and dont really see any scratches, its just normal looking nothing abnormal.

so I'm just considering a steel one, last models I've never had issues with steel spurs. In my opinion as long as your mesh is correct the steel ones will last for along long time.

 

[Assassin]

but how would the spur gear cause more air/fuel to enter the engine to make it rev higher ? It didnt seem to rev wide open untill i just barley tapped the gas.

That's what it sounds like when you burn a spur, sudden loss of resistance as the spur or cb burn out. You tap the gas and it revs up really high really fast, usually right after the gear is burnt, any tapping of the gas will make it rev up MUCH faster than if there were resistance from the drive train.

Did that make your servo stick open, who knows unless you can repeat the issue it could of just been one of those things, especially since you say t doesn't happen anymore. What can we tell you aside for it's impossible for us to know and you have to see it happen again and analyze the conditions it occurs.

 

[TRXaddict]

That's what it sounds like when you burn a spur, sudden loss of resistance as the spur or cb burn out. You tap the gas and it revs up really high really fast, usually right after the gear is burnt, any tapping of the gas will make it rev up MUCH faster than if there were resistance from the drive train.

Did that make your servo stick open, who knows unless you can repeat the issue it could of just been one of those things, especially since you say t doesn't happen anymore. What can we tell you aside for it's impossible for us to know and you have to see it happen again and analyze the conditions it occurs.

Its just it was different in all the other trucks I've owned, instead of it doing what the savage did it would be more like when i would climb a hill or something like that it would be like revving pretty high then just hear that sound that instantly tells you its burned. Then it does have that feeling when it has no load where it just is really touchy and revs fast but in those it never stayed wide open for me.

Maybe it was just a freak think that happened but luckly, its a cheap part thats supposed to go out from time to time. and soon ill be getting a steel one. with my past trucks I've never had any problems with steel spurs so i figure this is just an opportunity to upgrade one more thing.

Probably gonna get this http://cgi.ebay.com/ws/eBayISAPI.dl...gory=34061&_trksid=p5197.c0.m619#ht_995wt_750

my mother actually happens to be in the city at the moment so i might ask her to just stop at the hobby shop down there and pick one up.. after market or not ill take anything at the moment.. i wanna drive.

*EDIT* i can't believe this i calledl ike 4 diff shops not one of them even had a stock savage spur gear.... surprised that they didnt have any but almost all of them said they dont carry really any HPI products.

 

[TRXaddict]

Ok finally got the video to work.. poor quality but yeah and my driving isnt good with one hand but heres what happend.http://www.youtube.com/watch?feature=player_embedded&v=YXFjgAtll9A

 

[MudSlinger33]

I see what you are talking about now. The only things I could think of that happened was a glitch in the radio/servo or the servo got hung up on something. Looks like a fun place to bash though.

 

[TRXaddict]

Thanks, yeah its a pretty fun place.. it was better but some kids on bmx bikes came and defaced the whole track so now there are only like 2 turns left. and broke the plywood ramp i had in the video in half. But I'm going to try to rebuild it soon, and just try to get someone to record me while driving because its really hard for me atleast to hold the camera and drive lol.

But yeah maybe it was just a freak accident where it just decided to hold wide open.

 

[Phins Fan]

While I would think a glitching issue with the am radio it didnt really appear or sound like that may be the issue. I know you said all the batteries were fully charged. Is it possible you have some frayed or split servo wires somewhere? Just thinking it could have crapped out just as you hit the throttle and didnt restablish contact to close the servo. Do you have a throttle return spring on it?

 

[Snook Man]

The engine reved high after the spur stripped because the tune was off. You were running pretty lean throughout. The lean condition caused the high idle speed; once the spur stripped, the engine was free to spool up because there was not resistance from the spur to hold it back. That wasn’t anywhere near WOT when the spur stripped.

 

[TRXaddict]

While I would think a glitching issue with the am radio it didnt really appear or sound like that may be the issue. I know you said all the batteries were fully charged. Is it possible you have some frayed or split servo wires somewhere? Just thinking it could have crapped out just as you hit the throttle and didnt restablish contact to close the servo. Do you have a throttle return spring on it?

Yeah when i turned it off i checked the servo and was pressing fullbrake to full throttle and it was performing fine. no pulsing or jittering. and then after i took the throttle servo out and reconnected it, it still performed fine. I did how ever just in case put the stock servo in there. ( and also the spring was attached)

Not sure if you seen it but i did replace the stock throttle servo with the stock steering servo after i upgraded my steering servo with a 255 oz. I did this because i read up and apparently do this increases your braking power and it really did. I noticed a very strong brake after doing this and i guess it was too strong anyways because the swap did make me sometimes flip frontward just driving on the ground even on dirt.


Also i think another thing that happened is since the steering servo is a much lower gearing when you have the receiver off and open the throttle the spring isnt strong enough to pull the slide back shut.. I think some how it glitched and then the spring wasn't strong enough to pull the throttle back closed because that servo is very strong compared to stock throttle servo.

Thats really my only assumption. still dont know why i was able to drive for over 2 hours and not have one issue or glitchy servo the whole time untill i recorded it. Its not possible for the camera to interfere right ? other than that i dont know what exactly caused it to hold wide open. but i do believe once it got wide open the spring couldnt pull it back shut.

The engine reved high after the spur stripped because the tune was off. You were running pretty lean throughout. The lean condition caused the high idle speed; once the spur stripped, the engine was free to spool up because there was not resistance from the spur to hold it back. That wasn’t anywhere near WOT when the spur stripped.

But how would a tune effect the spur gear to strip just from sitting at idle ? I can imagine maybe being to lean and like climbing the hill climb but i can't imagine it stripping just from sitting and slowly taking off.

Also i know where your coming from about the engine having no load and revving but in my opinion it wouldnt rev like that with the throttle closed.

Also it sounded wide open to me, it may not sound that loud on the video but being there it was very very loud. That type of loud that actually is alittle scary walking up to as it was sitting there.

Also, the gear wasn't fully stripped. It was only about 1 inch stripped and it would have gone further but i stopped it before it could go all around. Witch tells me that there was still load on the engine because it was just holding wide open while somehow being held still and then just sort of ripping through teeth while doing so.

 

[Snook Man]

I never said the tune caused the spur to strip.
1st of all you can not strip/break a savage spur with just the engine torque alone when meshed correctly. Even if the truck is stuck against a wall, slipper fully locked and you hold it WOT the engine just isn’t strong enough to break the teeth that way.
The spur most likely didn’t strip when it was sitting there.
You most likely broke a tooth or 2 while running it just prior to when you sat the camera down. At that point you can hear the RPM’s raise from the already high idle, the extra rpms rotated the spur to the broken tooth area and then the remaining (now missing) teeth broke and the rpms really took off.

It may have sounded loud but it wasn’t by any means WOT IMHO.